A lighting unit in which various light sources used in electronic devices are utilized has been implemented in such a manner as to increase light efficiency by utilizing an appropriate light source according to each property of the electronic devices.
The lighting unit recently used in the electronic devices may be variously applied to a backlight unit applied to a flat display, an indoor light used in indoor environments, a headlight, a fog light, a backlight, a sidelight, a license plate light, a taillight, a stop light, a turn signal light, and a hazard flasher lamp installed at the outside of a vehicle, an indoor illumination lamp installed inside a vehicle, or the like.
However, the most of illumination is mainly realized by a method of increasing luminance of a surface light source by applying a member such as a light guide plate for enabling the efficient transmission of light.
However, in the case of a specific illuminating device such as an illuminating device for a vehicle which should meet the legal condition of the distribution of light, when the surface light source is applied to the device, it is difficult to adjust the distribution of light in implementing illumination realized by the conventional method of increasing luminance with the surface light source. In particular, since a light concentration level is reduced, there is a limit in applying the surface light source as illumination.